function s1_hello() {
    echo "hello, world!"
}
function s2_tell_who_i_am() {
    echo $(whoami)
}
function s3_which_distro_do_i_use() {
    grep ^NAME= /etc/os-release
}
function s4_view_my_cpu_arch() {
    uname -m
}

function s5_show_first_scsi_disk_size() {
    local size=$(blockdev --getsize64 /dev/sda)
    echo $((size / 1073741824))  # 转换为GB
}
function s6_show_main_memory_size_in_megabytes() {
    free -m | grep "Mem:" | awk '{print $2}'
}
